Analysis of Once-Daily Thoracic Radiotherapy Dose According to the Underlying Lung Disease in Patients with Limited-Stage Small Cell Lung Cancer Undergoing Concurrent Chemoradiotherapy / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#In the treatment of concurrent chemoradiotherapy (CCRT) in limited-stage small cell lung cancer, the optimal once-daily radiotherapy (RT) dose/fractionation remain unclear although it is the most frequently used. Therefore, this study aimed to compare the treatment outcomes and toxicities of modest dose RT (≤ 54 Gy) with those of standard dose RT (> 54 Gy) and investigate the benefit of the high dose based on patient factors. @*Materials and Methods@#Since 2004, our institution has gradually increased the thoracic RT dose. Among the 225 patients who underwent CCRT, 84 patients (37.3%) received > 54 Gy. Because the patients treated with RT > 54 Gy were not randomly assigned, propensity score matching (PSM) was performed. @*Results@#The proportion of patients treated with > 54 Gy increased over time (p=0.014). Multivariate analysis revealed that the overall tumor stage and dose > 54 Gy (hazard ratio, 0.65; p=0.029) were independent prognostic factors for overall survival (OS). PSM confirmed that thoracic RT doses of > 54 Gy showed significantly improved progression-free survival (3-year, 42.7% vs. 24.0%; p 54 Gy was not observed but considerable rates of severe pulmonary toxicities were observed (p=0.001). @*Conclusion@#Our analysis supports that the 60 Gy RT dose should be considered in the once-daily regimen of CCRT for limited-stage small cell lung cancer without underlying lung disease, but RT dose > 54 Gy did not seem to benefit for patients with chronic obstructive pulmonary disease or interstitial lung disease. Further study is needed to validate these results.

Exploring the past, present, and future of postoperative radiotherapy for N2 stage non-small cell lung cancer

Despite conventionally applied postoperative radiotherapy (PORT) in pathological N2 (pN2) stage non-small cell lung cancer (NSCLC) considering high locoregional recurrence, its survival benefit has been a continuous topic of debate. Although several randomized clinical trials have been conducted, many of them have been withdrawn or analyzed without statistical significance due to slow accrual, making it difficult to determine the efficacy of PORT. Recently, the results of large-scale randomized clinical trials have been published, which showed some improvement in disease-free survival with PORT, but finally had no impact on overall survival. Based on these results, it was expected that the debate over PORT in pN2 patients with NSCLC would come to an end. However, since pN2 patients have different clinicopathologic features, it has become more important to carefully select the patient population who will benefit from PORT. In addition, given the development of systemic treatments such as molecular-targeted therapy and immunotherapy, it is crucial to evaluate whether there is any benefit to PORT in the midst of these recent changes. Therefore, determining the optimal treatment approach for NSCLC pN2 patients remains a complex issue that requires further research and evaluation.

Clinical outcomes of radical radiotherapy for pulmonary sarcomatoid carcinoma

Purpose@#Pulmonary sarcomatoid carcinoma (PSC) is recognized for its aggressiveness and poor prognosis. The role of radical radiotherapy in PSC remains uncertain due to its scarcity and limited data. In the absence of an effective systemic agent, this study aims to explore the possibility of cure and to investigate potential prognostic factors and treatment outcomes. @*Materials and Methods@#From January 2005 to December 2021, 149 PSC patients were identified. Among 62 patients who received radiotherapy for lung lesions, 25 who underwent palliative radiotherapy and 16 who underwent surgery were excluded. @*Results@#The median patient age was 71 years. The majority were male, and 17 patients (81.0%) were diagnosed at an advanced stage. After radical radiotherapy, distant metastasis (47.6%) was the most common site of failure, while the local recurrence rate was quite low (9.5%). Eventually, five patients (26.3%) demonstrated either a partial response or complete remission, including three complete remissions with durable responses. The median progression-free survival (PFS) and overall survival were 4.6 months and 7.9 months, respectively. Univariate and multivariate analyses revealed that a tumor size >5 cm was associated with a worse prognosis (p = 0.045), while a radiation dose >58 GyEQD2 was significantly associated with better PFS (p = 0.038). @*Conclusion@#This study demonstrates clinical outcomes after radical radiotherapy in managing PSC, suggesting tumor size and radiation dose could be a predictor of a systemic response. Given the known bad prognosis but complete remission could be achieved in certain subgroups, future research should explore the potential strategies using radical radiotherapy for this challenging patient population.

Prognostic Implication of Focal Breast Edema on Preoperative Breast Magnetic Resonance Imaging in Breast Cancer Patients / 한국유방암학회지

Purpose@#In this study, we investigated the prognostic implications of focal breast edema on preoperative breast magnetic resonance imaging (MRI) in patients with breast cancer. @*Methods@#Data of 899 patients with breast cancer at a single institution were retrospectively analyzed. The patients were divided into an edema-positive group (EPG) and an edemanegative group (ENG) based on the presence of peritumoral, prepectoral, or subcutaneous edema. Two radiologists evaluated the presence or absence of focal edema and its subtypes on preoperative breast MRI. Clinicopathologic characteristics and survival outcomes were compared between the two groups and among the three subtypes using Pearson’s χ2 test, Kaplan–Meier estimator, and Cox proportional hazards model. @*Results@#There were 399 (44.4%) and 500 (55.6%) patients in the EPG and ENG, respectively.The EPG showed significantly higher rates of axillary lymph node metastasis (55.6% vs.19.2%, p < 0.001) and lymphovascular invasion (LVI) (57.9% vs. 12.6%, p < 0.001) than the ENG. Patients in the EPG showed significantly worse overall survival (OS) rate (log-rank p < 0.001; hazard ratio [HR], 4.83; 95% confidence interval [CI], 2.56–9.11) and recurrencefree survival rate (log-rank p < 0.001; HR, 3.00; 95% CI, 1.94–4.63) than those in the ENG.After adjusting for other variables, focal breast edema remained a significant factor affecting the OS rate, regardless of the edema type. Specifically, the presence of subcutaneous edema emerged as the strongest predictor for OS with the highest HR (p < 0.001; HR, 9.10; 95% CI, 3.05–27.15). @*Conclusion@#Focal breast edema on preoperative breast MRI implies a higher possibility of LVI and axillary lymph node metastasis, which can lead to a poor prognosis. A detailed description of focal breast edema, especially subcutaneous edema, on preoperative breast MRI may provide prognostic predictions. More intensive surveillance is required for patients with breast cancer and focal preoperative breast edema.

Efficacy of Prophylactic Cranial Irradiation According to the Risk of Extracranial Recurrence in Limited-Stage Small Cell Lung Cancer / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#We aimed to evaluate the effectiveness of prophylactic cranial irradiation (PCI) for “early brain metastasis”, which occurs before extracranial recurrence (ECR), and “late brain metastasis”, which occurs after ECR, in limited-stage small cell lung cancer (LS-SCLC). @*Materials and Methods@#We retrospectively analyzed 271 LS-SCLC patients who underwent definitive chemoradiation. All patients were initially staged with brain magnetic resonance imaging and positron emission tomography. Intracranial recurrence (ICR), ECR, progression-free rate (PFR), and overall survival (OS) were analyzed as clinical endpoints. The competing risk of the first recurrence with ICR (ICRfirst) was evaluated. Significantly associated variables in multivariate analysis of ECR were considered as ECR risk factors. Patients were stratified according to the number of ECR risk factors. @*Results@#The application of PCI was associated with higher PFR (p=0.008) and OS (p=0.045). However, PCI was not associated with any of the clinical endpoints in multivariate analysis. The competing risk of ICRfirst was significantly decreased with the application of PCI (hazard ratio, 0.476; 95% confidence interval, 0.243 to 0.931; p=0.030). Stage III disease, sequential, and stable disease after thoracic radiation were selected as ECR risk factors. For patients without these risk factors, the application of PCI was significantly associated with increased OS (p=0.048) and a decreased risk of ICRfirst (p=0.026). @*Conclusion@#PCI may play a role in preventing early brain metastasis rather than late brain metastasis after ECR, suggesting that only patients with a low risk of ECR may currently benefit from PCI.

Reduced-dose whole-brain radiotherapy with tumor bed boost after upfront high-dose methotrexate for primary central nervous system lymphoma

Purpose@#This retrospective study compares higher-dose whole-brain radiotherapy (hdWBRT) with reduced-dose WBRT (rdWBRT) in terms of clinical efficacy and toxicity profile in patients treated for primary central nervous system lymphoma (PCNSL). @*Materials and Methods@#Radiotherapy followed by high-dose methotrexate (HD-MTX)-based chemotherapy was administered to immunocompetent patients with histologically confirmed PCNSL between 2000 and 2016. Response to chemotherapy was taken into account when prescribing the radiation dose to the whole brain and primary tumor bed. The whole brain dose was ≤23.4 Gy for rdWBRT (n = 20) and >23.4 Gy for hdWBRT (n = 68). Patients manifesting cognitive disturbance, memory impairment and dysarthria were considered to have neurotoxicity. A median follow-up was 3.62 years. @*Results@#The 3-year overall survival (OS) and progression-free survival (PFS) were 70.0% and 48.9% with rdWBRT, and 63.2% and 43.2% with hdWBRT. The 3-year OS and PFS among patients with partial response (n = 45) after chemotherapy were 77.8% and 53.3% with rdWBRT, and 58.3% and 45.8% with hdWBRT (p > 0.05). Among patients with complete response achieved during follow-up, the 3-year freedom from neurotoxicity (FFNT) rate was 94.1% with rdWBRT and 62.4% with hdWBRT. Among patients aged ≥60 years, the 3-year FFNT rate was 87.5% with rdWBRT and 39.1% with hdWBRT (p = 0.49). Neurotoxicity was not observed after rdWBRT in patients aged below 60 years. @*Conclusion@#rdWBRT with tumor bed boost combined with upfront HD-MTX is less neurotoxic and results in effective survival as higher-dose radiotherapy even in partial response after chemotherapy.

Identifying Long-Term Survival Candidates among Patients with Isolated Locoregionally Recurrent Breast Cancer: Implications of the Use of Systemic Chemotherapy / 한국유방암학회지

Purpose@#We aimed to investigate the clinicopathologic factors associated with distant metastasis (DM) and post-recurrence overall survival (OS) after salvage treatments for isolated locoregional recurrence (ILRR) of breast cancer and identify long-term surviving patients for providing a more personalized therapy. @*Methods@#We analyzed 125 patients who underwent salvage local treatments for ILRR after initial curative breast surgery. @*Results@#Fifty-two (41.6%) patients experienced secondary recurrence or disease progression, of which 20 (38.5%) experienced a secondary locoregional recurrence and 40 (76.9%) experienced DM as the first site of failure. In multivariate analysis of distant metastasis free survival (DMFS) and post-recurrence OS, the initial pN2-3 stage, a disease-free interval of < 36 months, and non-curative resection for recurrent disease were independently poor prognosticators. The score for patients stratified according to the number of risk factors increased from 0 to 3; the corresponding 5-year DMFS rates were 91.4%, 53.0%, 35.9%, and 0% and the 5-year OS rates were 97.3%, 70.4%, 32.7%, and 25.0%, respectively (p < 0.001).Systemic chemotherapy reduced DM in patients with a score of 2–3, but it did not in those with a score of 0-1. @*Conclusion@#Our collective stratification can help with prognosis prediction for ILRR of breast cancer. Depending on the DM risk of patients, the potential combination of systemic therapy should be discussed further.

Prognostic Role of KRAS mRNA Expression in Breast Cancer / 한국유방암학회지

Evaluation of the Benefit of Radiotherapy in Patients with Occult Breast Cancer: A Population-Based Analysis of the SEER Database / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Few studies for occult breast cancer (OBC) have evaluated the effect of radiotherapy (RT) after mastectomy or axillary lymph node dissection (ALND) with/without breast surgery. Therefore, we investigated clinicopathologic factors of OBC with the impact of postoperative RT to determine its prognostic significance using large population-based data. MATERIALS AND METHODS: We performed a retrospective cohort study using the Surveillance, Epidemiology, and End Results (SEER) database from 1983 to 2013. A total of 1,045 eligible patients with OBC were identified. We compared overall survival (OS) using Cox proportional hazards regression with propensity score matching after verifying an imbalance of prognosticators between RT group (n=518) and non-RT group (n=479). RESULTS: Patients with age < 70 (p=0.033), married marital status (p < 0.001), undergoing ALND (p < 0.001), more examined lymph nodes (LNs) (p < 0.001), and more metastatic LNs (p < 0.001) were more likely to receive RT. Multivariate analysis after propensity score matching (n=798) showed that patients treated with RT survived significantly longer than those without RT (5-year OS, 81.5% vs. 78.3%; p=0.014). A significantly prolonged OS was observed when RT was given to patients treated with mastectomy (p=0.033), those treated with ALND (p=0.036), or those with more than seven metastatic LNs (p=0.016). CONCLUSION: RT may offer survival benefit in OBC even after mastectomy or ALND, especially in patients with more than seven metastatic LNs. Further prospective studies are needed to validate these findings.

Long-Term Outcome of Distal Cholangiocarcinoma after Pancreaticoduodenectomy Followed by Adjuvant Chemoradiotherapy: A 15-Year Experience in a Single Institution / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: This study was conducted to evaluate the long-term outcome in patients undergoing pancreaticoduodenectomy (PD) followed by adjuvant chemoradiotherapy for distal cholangiocarcinoma (DCC) in a high-volume center and to identify the prognostic impact of clinicopathologic factors. MATERIALS AND METHODS: A total of 132 consecutive patients who met the inclusion criteria were retrieved from the institutional database from January 1995 to September 2009. All patients received adjuvant treatments at a median of 45 days after the surgery. Median follow-up duration was 57 months (range, 6 to 225 months) for all patients and 105 months for survivors (range, 13 to 225 months). RESULTS: The 5-year locoregional recurrence-free survival (LRRFS), distant metastasis-free survival (DMFS), disease-free survival (DFS), and overall survival (OS) rates were 70.7%, 55.7%, 49.4%, and 48.1%, respectively. Univariate analysis revealed poorly differentiated (P/D) tumors and lymph node (LN) metastasis were significantly associated with DMFS and OS. Additionally, preoperative carbohydrate antigen 19-9 level was significantly correlated with DFS, LRRFS, and DMFS. Upon multivariate analysis for OS, P/D tumors (p=0.015) and LN metastasis (p=0.003) were significant prognosticators that predicted inferior OS. Grade 3 or higher late gastrointestinal toxicity occurred in only one patient (0.8%). CONCLUSION: Adjuvant chemoradiotherapy after PD for DCC is an effective and tolerable strategy without significant side effects. During long-term follow-up, we found that prognosis of DCC was mainly influenced by histologic differentiation and LN metastasis. For patients with these risk factors, further research should focus on improving adjuvant strategies as well as other treatment approaches.

A Prognostic Model for Patients with Triple-Negative Breast Cancer: Importance of the Modified Nottingham Prognostic Index and Age / 한국유방암학회지

PURPOSE: Considering the distinctive biology of triple-negative breast cancer (TNBC), this study aimed to identify TNBC-specific prognostic factors and determine the prognostic value of the Nottingham Prognostic Index (NPI) and its variant indices. METHODS: A total of 233 patients with newly diagnosed stage I to III TNBC from 2003 to 2012 were reviewed. We retrospectively analyzed the patients' demographics, clinicopathologic parameters, treatment, and survival outcomes. The NPI was calculated as follows: tumor size (cm)×0.2+node status+Scarff-Bloom-Richardson (SBR) grade. The modified NPI (MNPI) was obtained by adding the modified SBR grade rather than the SBR grade. RESULTS: The median follow-up was 67.8 months. Five-year disease-free survival (DFS) and overall survival (OS) were 81.4% and 89.9%, respectively. Multivariate analyses showed that the MNPI was the most significant and common prognostic factor of DFS (p=0.001) and OS (p=0.019). Young age (≤35 years) was also correlated with poor DFS (p=0.006). A recursive partitioning for establishing the prognostic model for DFS was performed based on the results of multivariate analysis. Patients with a low MNPI (≤6.5) were stratified into the low-risk group (p6.5) were subdivided into the intermediate (>35 years) and high-risk (≤35 years) groups. Age was not a prognostic factor in patients with a low MNPI, whereas in patients with a high MNPI, it was the second key factor in subdividing patients according to prognosis (p=0.023). CONCLUSION: The MNPI could be used to stratify patients with stage I to III TNBC according to prognosis. It was the most important prognosticator for both DFS and OS. The prognostic significance of young age for DFS differed by MNPI.

Objective Measurement of Cosmetic Outcomes of Breast Conserving Therapy Using BCCT.core / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The purpose of this study is to evaluate objective cosmetic outcomes and factors related to breast-conserving therapy (BCT) using the BCCT.core software. MATERIALS AND METHODS: Fifty-one patients who received BCT with informed consent were evaluated using the BCCT.core software. Patients were divided into two groups based on the BCCT score: excellent or good (n=42) vs. fair or poor (n=9). Analysis of clinical factors was performed to determine factors affecting cosmetic outcomes. RESULTS: The objective cosmetic outcome of BCT measured using the BCCT.core software was excellent in 10% of patients, good in 72%, and fair in 18%. None of the patients were classified as poor outcome. Tumor characteristics, systemic adjuvant therapy (chemotherapy and hormonal therapy), and radiation dose or energy of electron boost did not show correlation with the score measured by the BCCT.core program (p > 0.05). In univariate analysis, maximum dose within the breast (Dmax), width of tangential field, and excised tumor volume were smaller in patients with excellent or good by the BCCT.core compared to those with fair or poor (Dmax, 110.2±1.5% vs. 111.6±1.7%, p=0.019; width of tangential field, 8.0±1.1 cm vs. 8.6±0.7 cm, p=0.034; excised tumor volume, 64.0±35.8 cm3 vs. 95.3±54.4 cm3, p=0.067). In multivariate analysis, only Dmax was a significant factor for breast cosmetic outcome with a risk ratio of 1.697 (95% confidence interval, 1.006 to 2.863; p=0.047). CONCLUSION: Objective measurement of cosmetic outcome of BCT using the BCCT.core software was feasible. The cosmetic outcome of BCT may be affected by the maximum dose within the breast.

Prognostic Value of Splenic Artery Invasion in Patients Undergoing Adjuvant Chemoradiotherapy after Distal Pancreatectomy for Pancreatic Adenocarcinoma / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The purpose of this study was to evaluate the outcome of adjuvant chemoradiotherapy (CRT) after distal pancreatectomy (DP) in patients with pancreatic adenocarcinoma, and to identify the prognostic factors for these patients. MATERIALS AND METHODS: We performed a retrospective review of 62 consecutive patients who underwent curative DP followed by adjuvant CRT between 2000 and 2011. There were 31 men and 31 women, and the median age was 64 years (range, 38 to 80 years). Adjuvant radiotherapy was delivered to the tumor bed and regional lymph nodes with a median dose of 50.4 Gy (range, 40 to 55.8 Gy). All patients received concomitant chemotherapy, and 53 patients (85.5%) also received maintenance chemotherapy. The median follow-up period was 24 months. RESULTS: Forty patients (64.5%) experienced relapse. Isolated locoregional recurrence developed in 5 patients (8.1%) and distant metastasis in 35 patients (56.5%), of whom 13 had both locoregional recurrence and distant metastasis. The median overall survival (OS) and disease-free survival (DFS) were 37.5 months and 15.4 months, respectively. On multivariate analysis, splenic artery (SA) invasion (p=0.0186) and resection margin (RM) involvement (p=0.0004) were identified as significant adverse prognosticators for DFS. Also, male gender (p=0.0325) and RM involvement (p=0.0007) were associated with a significantly poor OS. Grade 3 or higher hematologic and gastrointestinal toxicities occurred in 22.6% and 4.8% of patients, respectively. CONCLUSION: Adjuvant CRT may improve survival after DP for pancreatic body or tail adenocarcinoma. Our results indicated that SA invasion was a significant factor predicting inferior DFS, as was RM involvement. When SA invasion is identified preoperatively, neoadjuvant treatment may be considered.

Low-Dose Whole Brain Radiotherapy with Tumor Bed Boost after Methotrexate-Based Chemotherapy for Primary Central Nervous System Lymphoma / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The purpose of this study is to evaluate the outcome of low-dose whole brain radiotherapy (WBRT) with tumor bed boost after methotrexate-based chemotherapy in the management of primary central nervous system lymphoma (PCNSL). MATERIALS AND METHODS: We retrospectively analyzed 64 patients with pathologically proven PCNSL between 2000 and 2011. Methotrexate-based chemotherapy with a median of five cycles was followed by radiotherapy to the whole brain and to the initial tumor bed. The median dose to the whole brain and to the tumor bed was 27 Gy (range, 18 to 36 Gy) and 50.4 Gy (range, 45 to 54 Gy), respectively. RESULTS: With a median follow-up period of 27 months, 55 patients (85.9%) achieved complete response (CR). The 5-year overall survival (OS) and progression-free survival (PFS) rates were 52.6% and 39.3%, respectively. In univariate analysis, factors associated with OS were age, performance status, involvement of deep structure, and CR to sequential chemoradiotherapy (CRT). These variables remained as significant factors for OS in multivariate analysis. CR to sequential CRT was the only positive factor associated with PFS (p=0.009). Neurologic toxicity was more common in elderly patients older than 60 years (p=0.025). CONCLUSION: Low-dose WBRT with tumor bed boost after methotrexate-based chemotherapy might be an effective method for management of PCNSL.

Role of salvage radiotherapy for regional lymph node recurrence after radical surgery in advanced gastric cancer

PURPOSE: To evaluate the role of salvage radiotherapy (RT) for the treatment of regional lymph node recurrence (RLNR) after radical surgery in advanced gastric cancer. MATERIALS AND METHODS: We retrospectively analyzed medical records of 26 patients who underwent salvage treatment after diagnosis of RLNR between 2006 and 2011. Patients with peritoneal seeding or distant metastasis were excluded. Eighteen patients received RT with or without chemotherapy and the other 8 did chemotherapy only without RT. A three-dimensional conformal RT was performed with median dose of 56 Gy (range, 44 to 60 Gy). Sixteen patients had fluoropyrimidine-based chemotherapy, 5 did taxane-based chemotherapy, and irinotecan was applied in 4. RESULTS: With a median follow-up of 20 months (range, 5 to 57 months), median overall survival (OS) and progression-free survival (PFS) after diagnosis of RLNR were 29 months and 12 months in the entire patients, respectively. Radiotherapy (p = 0.007) and disease-free interval (p = 0.033) were statistically significant factors for OS in multivariate analysis. Median OS was 36 months in patients who received RT and 16 months in those who did not. Furthermore, delivery of RT (p < 0.001), complete remission after salvage treatment (p = 0.040) and performance status (p = 0.023) were associated with a significantly better PFS. Gastrointestinal toxicities from RT were mild in most patients. CONCLUSION: Salvage RT combined with systemic chemotherapy may be an effective treatment managing RLNR from advanced gastric cancer.